Endoscopic endonasal surgery for prolactinomas: prognostic factors for disease control and management of persistent disease.

Only a limited number of studies have focused on the results of the Endoscopic Endonasal Approach (EEA) for treatment of prolactinomas. We sought to assess the effectiveness of EEA for prolactinoma surgery, identify factors for disease remission, and present our approach for the management of persistent disease. Forty-seven prolactinomas operated over 10 years, with a mean follow-up of 59.9 months, were included. The primary endpoints were early disease remission and remission at last follow-up. Resistance/intolerance to DA were surgical indications in 76.7%. Disease remission was achieved in 80% of microprolactinomas and 100% of microprolactinomas enclosed by the pituitary. Early disease remission was correlated with female gender (p=0.03), lower preoperative PRL levels (p=0.014), microadenoma (p=0.001), lack of radiological hemorrhage (p=0.001), absence of cavernous sinus (CS) invasion (p<0.001), and extent of resection (EOR) (p<0.001). Persistent disease was reported in 48.9% of patients, with 47% of them achieving remission at last follow-up with DA therapy alone. Repeat EEA and/or radiotherapy were utilized in 6 patients, with 66.7% achieving remission. Last follow-up remission was achieved in 76.6%, with symptomatic improvement in 95.8%. Factors predicting last follow-up remission were no previous operation (p=0.001), absence of CS invasion (p=0.01), and EOR (p<0.001). Surgery is effective for disease control in microprolactinomas. In giant and invasive tumors, it may significantly reduce the tumor volume. A multidisciplinary approach may lead to long-term disease control in three-quarters of patients, with symptomatic improvement in an even greater proportion.

Different Approaches in Skull Base Surgery Carry Risks for Different Types of Complications.

Complications are not uncommon in the complex field of skull base surgery. The intrinsic relationship of lesions in this region to important neurovascular structures, dura mater, and bone may lead to significant morbidity and mortality. The evolution of endoscopic endonasal surgery has had a significant impact on this field as a less invasive option for treatment of selected lesions, but major morbidity may still occur; moreover, endoscopic approaches have been associated with higher rates of some specific complications, such as cerebrospinal fluid leaks. Based on a presented case report, the authors discuss the management of various complications associated with different approaches for resection of skull base malignancies, including epidural and intradural pneumocephalus, subdural hematoma, and subdural empyema. Important lessons learned by the senior author throughout more than 30 years of his skull base surgery practice are highlighted. The inherent risk of complications in skull base surgery emphasizes the importance of their avoidance, prevention, and learning from one's unfavorable experience so as not to repeat them.

Psychometric testing of the Skull Base Inventory health-related quality of life questionnaire in a multi-institutional study of patients undergoing open and endoscopic surgery.

PURPOSE: The skull base inventory (SBI) was developed to better assess health-related quality of life (HR-QOL) in patients with anterior and central skull base neoplasms treated by endoscopic and open approaches. The primary objective of this study was to prospectively assess the psychometric properties of the SBI. METHODS: This study is part of a multi-center study of patients undergoing endoscopic and open procedures completed between 2012 and 2018. Participants were eligible if they were over 18 years of age; had benign or malignant anterior, antero-lateral, or central skull base tumors; and required either an open or endoscopic skull base surgical approach. In order to assess the psychometric properties of the SBI, patients completed the instrument at six time points (preoperative, 2 weeks, 3 months, 6 months, 12 months postoperative). Patients also completed the Anterior Skull Base (ASB) questionnaire and the Sinonasal Outcome Test (SNOT-22) to allow comparison to the SBI. RESULTS: One hundred and eighty-seven patients were included across five centers, with 121 having an endoscopic procedure. Internal consistency (Cronbach's alpha = 0.95) and test-retest at 12 months and 12 months plus 2 weeks (intraclass correlation > 0.90) were excellent. Concurrent validity was demonstrated by very strong correlation between total SBI scores and ASB scores (r = 0.810 to 0.869, p < 0.001) and moderate correlation between nasal domain SBI scores and SNOT-22 scores (r = - 0.616 to - 0.738, p < 0.001). Convergent validity was demonstrated by moderate correlation between change in SBI scores and global QOL change (rs = 0.4942, p < 0.001). The minimally important clinical difference (global HR-QOL change of "a little better" or "a little worse") was 6.0. CONCLUSION: The SBI questionnaire is reliable and valid for patients treated by both endoscopic and open approaches and can be used for assessment of HR-QOL in these settings.

Endoscopic extra-capsular resection of a giant pituitary adenoma: how I do it.

BACKGROUND: Giant pituitary adenomas are characterized by their large size and potential to invade parasellar and suprasellar regions leading to visual decline and hypopituitarism. Thus, they remain a significant surgical challenge, and gross total removal is only achieved in the minority of cases. METHOD: We aim to describe the key surgical steps for endoscopic extra-capsular resection of a giant pituitary adenoma with the aim of achieving complete tumor resection with description of the relevant surgical anatomy, indications and limitations. CONCLUSION: Endoscopic extra-capsular resection of giant pituitary tumors when feasible allows for complete tumor resection, early identification of the gland and avoidance of manipulation of the optic apparatus.

Efficacy of stereotactic radiosurgery for radiation-induced meningiomas.

PURPOSE: Stereotactic radiosurgery is an established treatment option for sporadic meningiomas, though limited data exists for radiation-induced lesions. METHODS: Patients treated with cobalt-60 radiosurgery between October 2005 and December 2018 in an institutional registry were reviewed. Single fraction treatments were prescribed to the 50% isodose line. Lesions were deemed to be radiation-induced according to standard criteria previously established by Cahan et al. RESULTS: A total of 37 patients with 72 lesions were analysed. Median follow up per patient was 44 months (range, 1.4-150.7 months). Median age at initial radiotherapy was 5 years (4 months-48 years), and at radiosurgery was 38 years. Of the 72 lesions, 62 were grade 1 (n = 4) or radiologically-diagnosed (n = 58), six were grade 2 and four were grade 3. Median lesion volume was 2.13 cc (0.04-13.8 cc), while the median radiosurgery margin dose was 13 Gy. Local control, on a per lesion basis, was 88.6% at 5 years (95% confidence interval [CI] 72.3-95.6). For grade 1 or radiologically-diagnosed lesions, local control was 96.6% at 5 years (95% CI 77.9-99.5), whereas those with grade 2 or higher lesions had a local control of 40% at 5 years (95% CI 5.2-75.3, p = 0.005). Radiologic oedema developed in 17 lesions (23.6%) and was symptomatic in 12 patients (16.7%). Doses above 12 Gy were not associated with local control probability (p = 0.292). CONCLUSION: Radiosurgery is an effective treatment option for grade 1 or radiologically-diagnosed radiation-induced meningiomas, with 12 Gy appearing to be a sufficient dose.

Quantitative anatomical comparison of transnasal and transcranial approaches to the clivus.

BACKGROUND AND OBJECTIVE: The clivus was defined as "no man's land" in the early 1990s, but since then, multiple approaches have been described to access it. This study is aimed at quantitatively comparing endoscopic transnasal and microsurgical transcranial approaches to the clivus in a preclinical setting, using a recently developed research method. METHODS: Multiple approaches were performed in 5 head and neck specimens that underwent high-resolution computed tomography (CT): endoscopic transnasal (transclival, with hypophysiopexy and with far-medial extension), microsurgical anterolateral (supraorbital, mini-pterional, pterional, pterional transzygomatic, fronto-temporal-orbito-zygomatic), lateral (subtemporal and subtemporal transzygomatic), and posterolateral (retrosigmoid, far-lateral, retrolabyrinthine, translabyrinthine, and transcochlear). An optic neuronavigation system and dedicated software were used to quantify the working volume of each approach and calculate the exposure of different clival regions. Mixed linear models with random intersections were used for statistical analyses. RESULTS: Endoscopic transnasal approaches showed higher working volume and larger exposure compared with microsurgical transcranial approaches. Increased exposure of the upper clivus was achieved by the transnasal endoscopic transclival approach with intradural hypophysiopexy. Anterolateral microsurgical transcranial approaches provided a direct route to the anterior surface of the posterior clinoid process. The transnasal endoscopic approach with far-medial extension ensured a statistically larger exposure of jugular tubercles as compared with other approaches. Presigmoid approaches provided a relatively limited exposure of the ipsilateral clivus, which increased in proportion to their invasiveness. CONCLUSIONS: This is the first anatomical study that quantitatively compares in a holistic way exposure and working volumes offered by the most used modern approaches to the clivus.

Clinical, pathologic, and imaging characteristics of pituitary null cell adenomas as defined according to the 2017 World Health Organization criteria: a case series from two pituitary centers.

PURPOSE: The 2017 World Health Organization classification of pituitary tumors redefined pituitary null cell adenomas (NCAs) by restricting this diagnostic category to pituitary tumors that are negative for pituitary transcription factors and adenohypophyseal hormones. The clinical behavior of this redefined entity has not been widely studied, and this is a major shortcoming of the classification. This study evaluated the imaging and clinical features of NCAs from two pituitary centers and compared them with those of gonadotroph adenomas (GAs). METHODS: Imaging, pathologic, and clinical characteristics of NCAs and GAs were retrospectively reviewed. Tumor immunohistochemistry was performed to confirm absence of adenohypophyseal hormones and pituitary transcription factor expression. RESULTS: Thirty-one NCAs were compared with 38 GAs. NCAs were more likely to invade the cavernous sinus (15/31 [48%] vs. 5/38 [13%], P = .003) and had a higher proliferative index (i.e., MIB-1 > 3%, 11/31 [35%] vs. 5/38 [13%], P = .04). Gross total resection was less likely in the NCA group (19/31 [61%] vs. 33/38 [87], P = .02). Progression-free survival was worse in the NCA cohort (5-year progression-free survival, 0.70 vs. 1.00; P = .011, by log-rank test). CONCLUSIONS: Compared with GAs, NCAs are more invasive at the time of presentation and have a more aggressive clinical course. This study provides evidence that NCAs represent a distinct clinicopathologic entity with behavior that differs adversely from that of GAs. This may inform clinical decision-making, including frequency of postoperative tumor surveillance and timing of adjunctive treatments.

Endonasal and Transoral Approaches to the Craniovertebral Junction: A Quantitative Anatomical Study.

BACKGROUND: The endoscopic endonasal approach has recently been added to the surgical armamentarium to access the anterior craniovertebral junction (CVJ). Comparative analyses with the transoral approach are scarce. The aim of this study was to provide a quantitative anatomical analysis of both approaches. METHODS: In four specimens the endoscopic endonasal approach (before and after sphenoidectomy) and the transoral approach (without and with a soft palate split) were performed. ApproachViewer-part of GTx-UHN (Guided Therapeutics software, developed at University Health Network, Toronto, ON, Canada)-was used to quantify and visualize the working volume, as well as the exposed area, of each surgical approach. Different modalities (crossing and non-crossing) were used to quantify the exposure of the deep surface, providing an indirect quantitative value of the 'surgical freedom'. The lowest point exposed by the endonasal approaches was compared with that predicted by preoperative radiological lines. Non-parametric Welch analysis of variance (ANOVA) was used for statistical analyses. RESULTS: The working volume was significantly larger and the distance to the target was shorter with the transoral approaches than with the endonasal approaches. Clival exposure was better with the endonasal approaches than with the non-crossing transoral approach without a soft palate split; areas below C1 were better exposed with the transoral routes. The nasoaxial line best predicted surgical exposure with the endonasal approaches. CONCLUSION: Endoscopic endonasal and transoral approaches to the anterior CVJ provide optimal exposure of different areas that overlap at the level of C1 when no anatomical anomalies are present. A split of the soft palate is not necessary during the transoral approach if it is combined with an endoscopic endonasal approach.

Silent subtype 3 pituitary adenomas are not always silent and represent poorly differentiated monomorphous plurihormonal Pit-1 lineage adenomas.

Originally classified as a variant of silent corticotroph adenoma, silent subtype 3 adenomas are a distinct histologic variant of pituitary adenoma of unknown cytogenesis. We reviewed the clinical, biochemical, radiological, immunohistochemical and ultrastructural features of 31 silent subtype 3 adenomas to clarify their cellular origin. Among 25 with clinical and/or radiological data, all were macroadenomas; there was cavernous sinus invasion in 30% of cases and involvement of the clivus in 17% of cases. Almost 90% of patients were symptomatic; 67% had mass effect symptoms, 37% were hypogonadal and 8% had secondary adrenal insufficiency. Significant hormonal excess in 29% of cases included hyperthyroidism in 17%, acromegaly in 8% and hyperprolactinemia above 150 µg/l in 4%. Two individuals with hyperprolactinemia who were younger than 30 years had multiple endocrine neoplasia type 1. Immunohistochemically, all 31 tumors were diffusely positive for the pituitary lineage-specific transcription factor Pit-1. Although three only expressed Pit-1, others revealed variable positivity for one or more hormones of Pit-1 cell lineage (growth hormone, prolactin, thyroid-stimulating hormone), as well as alpha-subunit and estrogen receptor. Most tumors exhibited perinuclear reactivity for keratins with the CAM5.2 antibody; scattered fibrous bodies were noted in five (16%) tumors. The mean MIB-1 labeling index was 4% (range, 1-9%). Fourteen cases examined by electron microscopy were composed of a monomorphous population of large polygonal or elongated cells with nuclear spheridia. Sixty-five percent of patients had residual disease after surgery; after a mean follow-up of 48.4 months (median 41.5; range=2-171) disease progression was documented in 53% of those cases. These data identify silent subtype 3 adenomas as aggressive monomorphous plurihormonal adenomas of Pit-1 lineage that may be associated with hyperthyroidism, acromegaly or galactorrhea and amenorrhea. Our findings argue against the use of the nomenclature 'silent' for these tumors. To better reflect the characteristics of these tumors, we propose that they be classified as 'poorly differentiated Pit-1 lineage adenomas'.

Non-contiguous meningeal metastases of olfactory neuroblastoma.

Olfactory neuroblastoma (ONB) is a malignant neoplasm centered along the roof of the nasal cavity near the cribriform plate. Although metastasis of this tumor has been reported, non-contiguous spread to the dura is rare. Here, we report the largest series of intracranial meningeal metastases of ONBs from M.D. Anderson Cancer Center and the University of Toronto. The unique natural history and geographical distribution of these metastatic lesions suggest a common mechanism of tumor spread along the dural vascular arborization.

Management and outcome of recurrent adult craniopharyngiomas: an analysis of 42 cases with long-term follow-up.

OBJECTIVE The treatment of recurrent and residual craniopharyngiomas is challenging. In this study the authors describe their experience with these tumors and make recommendations on their management. METHODS The authors performed an observational study of adult patients (≥ 18 years) with recurrent or residual craniopharyngiomas that were managed at their tertiary center. Retrospective data were collected on demographics and clinical, imaging, and treatment characteristics from patients who had a minimum 2-year follow-up. Descriptive statistics were used and the data were analyzed. RESULTS There were 42 patients (27 male, 15 female) with a mean age of 46.3 ± 14.3 years. The average tumor size was 3.1 ± 1.1 cm. The average time to first recurrence was 3.6 ± 5.5 years (range 0.2-27 years). One in 5 patients (8/42) with residual/recurrent tumors did not require any active treatment. Of the 34 patients who underwent repeat treatment, 12 (35.3%) had surgery only (transcranial, endoscopic, or both), 9 (26.5%) underwent surgery followed by adjuvant radiation therapy (RT), and 13 (38.2%) received RT alone. Eighty-six percent (18/21) had a gross-total (n = 4) or near-total (n = 14) resection of the recurrent/residual tumors and had good local control at last follow-up. One of 5 patients (7/34) who underwent repeat treatment had further treatment for a second recurrence. The total duration of follow-up was 8.6 ± 7.1 years. The average Karnofsky Performance Scale score at last follow-up was 80 (range 40-90). There was 1 death. CONCLUSIONS Based on this experience and in the absence of guidelines, the authors recommend an individualized approach for the treatment of symptomatic or growing tumors. This study has shown that 1 in 5 patients does not require repeat treatment of their recurrent/residual disease and can be managed with a "scan and watch" approach. On the other hand, 1 in 5 patients who had repeat treatment for their recurrence in the form of surgery and/or radiation will require further additional treatment. More studies are needed to best characterize these patients and predict the natural history of this disease and response to treatment.

Vascularized Nasoseptal Flap for Medial Orbital Wall Reconstruction.

With the use and efficacy of the vascularized nasoseptal flap, its indications are also expanding. Due to its relative ease of harvesting and no significant impairment in the long-term sinonasal quality of life, the flap has been used for a number of other purposes apart from its originally proposed use in reconstruction of the anterior cranial fossa, sella, and the clivus. Its use may negate the need of another incision to obtain fat or fascia. The authors describe the case of a 47-year-old lady who underwent endoscopic excision of a medially placed orbital intraconal hemangioma who presented to us with very poor vision in the left eye. The large medial orbital defect was reconstructed with a vascularized pedicled nasoseptal flap from the ipsilateral side. The patient made an excellent visual and sino-nasal recovery. This patient highlights a unique use for the proliferating indications for the use of the nasoseptal flap.

Chronic Rhinosinusitis With Massive Polyposis Causing Proptosis Requiring Craniofacial Resection.

Chronic rhinosinusitis (CRS) is a common health problem in the Western world. CRS is classified as CRS with (CRSwNP) and without (CRSsNP) nasal polyps. A less common third type is allergic fungal sinusitis, which often presents with polyps and, not infrequently, skull base erosion. Most patients are successfully managed with maximal medical therapy or endoscopic approaches. There are currently no reports of CRSwNPs resulting in fibro-osseous thickening and proptosis in the English literature. As such, the authors report a case of a 33-year-old man who underwent a craniofacial resection with drilling of the hyperostosed bone, which led to resolution of the proptosis and nasal symptoms. In an era where endoscopic surgery is the standard surgical approach for CRSwNP, this case highlights the need for open skullbase approaches for this condition due to the extensive and recalcitrant nature of the disease. While the majority of patients can be dealt with endoscopically, the authors highlight the importance of having the open approach in the otolaryngologists' armamentarium for patients of recalcitrant and extensive CRSwNP.

Proteins involved in regulating bone invasion in skull base meningiomas.

BACKGROUND: Bone invasive skull base meningiomas are a subset of meningiomas that present a unique clinical challenge due to brain and neural structure involvement and limitations in complete surgical resection, resulting in higher recurrence and need for repeat surgery. To date, the pathogenesis of meningioma bone invasion has not been investigated. We investigated immunoexpression of proteins implicated in bone invasion in other tumor types to establish their involvement in meningioma bone invasion. METHODS: Retrospective review of our database identified bone invasive meningiomas operated on at our institution over the past 20 years. Using high-throughput tissue microarray (TMA), we established the expression profile of osteopontin (OPN), matrix metalloproteinase-2 (MMP2), and integrin beta-1 (ITGB1). Differential expression in tumor cell and vasculature was evaluated and comparisons were made between meningioma anatomical locations. RESULTS: MMP2, OPN, and ITGB1 immunoreactivity was cytoplasmic in tumor and/or endothelial cells. Noninvasive transbasal meningiomas exhibited higher vascular endothelial cell MMP2 immunoexpression compared to invasive meningiomas. We found higher expression levels of OPN and ITGB1 in bone invasive transbasal compared to noninvasive meningiomas. Strong vascular ITGB1 expression extending from the endothelium through the media and into the adventitia was found in a subset of meningiomas. CONCLUSIONS: We have demonstrated that key proteins are differentially expressed in bone invasive meningiomas and that the anatomical location of bone invasion is a key determinant of expression pattern of MMP1, OPN, and ITGB1. This data provides initial insights into the pathophysiology of bone invasion in meningiomas and identifies factors that can be pursued as potential therapeutic targets.

Quality of life after transsphenoidal pituitary surgery: a qualitative study.

BACKGROUND: Microscopic and endoscopic approaches are both utilized for transsphenoidal resection of sellar/parasellar lesions. The endoscopic approach has been gaining popularity over the past decade; however, quality-of-life studies comparing the microscopic and endoscopic approaches are lacking. We aimed to compare the patients' perceptions of their postoperative recovery periods following microscopic and endoscopic procedures. METHODS: Qualitative research methodology was used for this study. Each participant underwent a single semi-structured, open-ended interview based on an interview guide. Each participant had undergone at least one microscopic and one endoscopic transsphenoidal procedure for resection of a sellar/parasellar lesion. The interviews were audiotaped and transcribed. The transcripts were then analyzed for overarching themes. Demographic information was also collected. RESULTS: The following five overarching themes emerged from the data: (1) the endoscopic procedure was better tolerated than the microscopic procedure and was the preferred approach by 22 out of 27 patients should they require another surgery in the future; (2) most patients did not know that they had undergone two different surgical approaches; (3) other than an unpleasant malodorous smell, rhinologic complications (including drainage, crusting, and alterations in smell) following the endoscopic procedures were comparable to those following the microscopic procedures; (4) the patient's postoperative experience after the microscopic procedure had an impact on his/her expectations of the endoscopic procedure; (5) any significant pain or discomfort experienced from either procedure was mainly related to the nasal packing or fascia lata graft donor site. CONCLUSIONS: The endoscopic procedure was the preferred approach over the microscopic approach by the majority of patients because of its better tolerability, despite comparable rhinologic complications.

Clinical features of silent corticotroph adenomas.

BACKGROUND: Silent corticotrph adenomas represent a distinct pathological subtype of non-functioning pituitary adenomas that are traditionally believed to carry a more aggressive biological behavior and higher potential for recurrence. METHODS: We conducted a retrospective review of all silent corticotroph adenomas treated and followed at our institution over the last 10 years. We reviewed clinical, radiological and pathological features. The series was compared to a matched cohort of ACTH-negative, non-functioning adenomas to compare clinical, radiological and pathological features. Our results were compared to the literature. RESULTS: Twenty patients met our inclusion criteria. Fifty-six percent of the patients were females. Mean age was 51 years (range 24-78 years). Visual dysfunction was the most common clinical presentation (38 %). Thirteen percent of the cases presented with acromegaly secondary to double adenoma (silent corticotroph adenoma and growth hormone adenoma) and 13 % presented with pituitary tumor apoplexy. All the tumors were macroadenomas. Frank cavernous sinus invasion occurred in 31 % of the cases. The patients who presented with acromegaly did not achieve remission postoperatively. In the remaining patients, recurrence occurred in 14 % of the cases over a mean follow-up period of 41 months. Compared to non-functioning adenomas, silent corticotroph adenomas were more likely to bleed (p value 0.014) and have double adenoma (p value 0.047). There was no difference in recurrence rates between silent corticotroph adenomas and non-functioning adenomas (p value 0.647). CONCLUSION: These results suggest that silent corticotroph adenomas have some unique features compared to non-functioning adenomas. Within the limits of our follow-up duration and sample size and our review of the literature, we would recommend that the traditional view to manage all silent corticotroph adenomas with adjuvant radiation should be reconsidered. We suggest adopting an initially more conservative follow-up surveillance and delay of upfront radiation until there is clear evidence of tumor recurrence.

Endoscopic Treatment of Sellar Arachnoid Cysts via a Simple Cyst-Opening Technique: Long-Term Outcomes From a Single Center.

BACKGROUND: Sellar arachnoid cysts (SACs) are rare lesions that require treatment only if symptomatic. The endoscopic endonasal approach has been widely used. Despite their simple cystic appearance and the straight-forward surgical intervention, important associated risks exist, with cerebrospinal fluid (CSF) leak the prevalent risk. METHODS: A retrospective analysis of patients with pathologically confirmed SAC between January 2006 and December 2019 was conducted. A homogeneous simple cyst-opening technique and skull base reconstruction with nasoseptal flaps was used. RESULTS: A total of 10 patients were identified (7 women and 3 men; median age, 54.5 years; range, 20-77 years). Of the 10 patients, 8 had had newly diagnosed SACs and 2 patients had had recurrence from a previously microsurgically fenestrated SAC. Eight patients had presented with visual symptoms, one with visual symptoms and fatigue, and one with intractable headaches. Neuro-ophthalmological and endocrinological assessments had revealed visual field deficits in 6, visual acuity decline in 5, and hypopituitarism in 2 patients. The median calculated volume was 1.71 mL (range, 0.27-2.54 mL). Postoperatively, no CSF leak and no further surgical complications were noted. The visual field had improved in 4 of 6 patients and visual acuity had improved in 4 of 5 patients. Anterior pituitary function had improved in 1, worsened in 1, and remained stable in 8 patients. One patient had developed diabetes insipidus. One recurrence was recorded at 54 months postoperatively. CONCLUSIONS: The results from the present study have shown that SACs can be effectively treated using a simple cyst-opening technique. The routine use of nasoseptal flaps significantly reduced the risk of CSF leakage without compromising nasal quality of life in the long term or mandating additional incisions. Long-term follow-up is important to monitor for late recurrence.

Endoscopic Treatment of Rathke's Cleft Cysts: The Case for Simple Fenestration.

BACKGROUND: Rathke's cleft cysts (RCC) arise from the pars intermedia because of incomplete regression of the embryologic Rathke pouch. A subset of RCC becomes symptomatic causing headaches, visual and endocrinological disturbances such that surgical intervention is indicated. Several points in surgical management remain controversial including operative strategy (simple fenestration (SF) vs complete cyst wall resection (CWR)) as well as reconstructive techniques. METHODS: A retrospective analysis was conducted of pathologically confirmed RCC operated on by endoscopic endonasal approach from 2006 to 2019. Pre-operative symptoms, imaging characteristics, operative strategy, symptom response, complications and recurrences were recorded. RESULTS: Thirty-nine patients were identified. Thirty-three underwent SF and six underwent CWR. Worsening pituitary function was significantly increased with CWR (50%) compared to SF (3%) (p = 0.008). All patients underwent "closed" reconstruction with a post-operative CSF leak rate of 5% (3% SF vs 16% CWR, p = 0.287). Six (15%) recurrences necessitating surgery were reported. Recurrence rates stratified by surgical technique (18% SF vs 0% CWR, p = 0.564) were not found to be significantly different. CONCLUSIONS: The current series illustrates variability in the surgical management of RCCs. SF with closed reconstruction is a reasonable operative strategy for most symptomatic RCCs cases while CWR can be reserved for selected cases.

Importance of Cobalt-60 Dose Rate and Biologically Effective Dose on Local Control for Intracranial Meningiomas Treated With Stereotactic Radiosurgery.

BACKGROUND: Radiosurgery dose rate and biologically effective dose (BED) are associated with outcomes after stereotactic radiosurgery (SRS) for functional neurosurgical conditions and some benign tumors. It is not known if these factors affect the efficacy of SRS for meningioma. OBJECTIVE: To determine the association between cobalt-60 dose rate and BED on outcomes in patients with meningioma treated with SRS. METHODS: A single-institution cohort of 336 patients treated between 2005 and 2018 with cobalt-based SRS for 414 separate meningioma lesions was assembled. BED was calculated using an SRS-specific monoexponential model accounting for treatment time per lesion, assuming α/ß = 2.47 Gy. Cumulative incidences of local failure (LF) were reported after considering the competing risk of death, on a per-lesion basis. Multivariable analysis of LF was performed using a proportional hazards model. RESULTS: The most common SRS dose was 12 Gy (n = 227); 140 lesions received 14 Gy. Five-year LF was 15.6% (95% confidence interval 10.4-21.9) and 4.3% (1.4-9.8) in patients who had a dose rate of <2.95 and ≥2.95 Gy/min, respectively (P = .0375). Among 354 grade I or unresected lesions treated with SRS, BED >50 Gy2.47 was associated with a lower incidence of LF (P = .0030). Each 1 Gy/min increase in dose rate was associated with an adjusted hazard ratio of 0.53 (95% confidence interval, 0.29-0.97, P = .041) for LF. Prescription dose >12 Gy was not associated with a lower incidence of LF. CONCLUSION: Patients with meningiomas treated with lower dose rates experienced a higher incidence of LF than those treated with higher dose rates.